The present invention relates to an original paper turning over and conveying out apparatus which is applied to a copying apparatus as an automatic original paper feeding and discharging device. More particularly, the invention relates to the original paper turning over and conveying out apparatus which is especially useful for an original paper circulation type copying apparatus.
Conventionally, an automatic original feeding and discharging device provided with a turn over operation mode is known. In the turn over operation mode, a conveyed original paper is turned over by switching back the paper to reverse the conveying direction thereof and discharged out of the device.
A conventional automatic original paper feeding and discharging device is described first hereinafter. The conventional device comprises a switch back conveyor route which is diverged sideward from a main conveyor route and dead ended to be used only for turning over an original in a turn over operation mode. Original papers to be copied are stacked on an original stacking table. An original paper is taken from the table and fed to a platen glass through a feeding conveyor route and exposed on the platen glass so that the original is copied. Then the original paper is conveyed along the main conveyor route and enters into the switch back conveyor route through a changing lever which is selected to guide the original paper to the diverged switch back conveyor route in the turn over operation mode. The original paper is switched back there so that the leading end and the following end of the paper is reversed thus reversing the upper surface and the lower surface thereof. After that, the turned over original paper is discharged from the switch back conveyor route through a discharge roller and returned to the original stacking table through another discharge roller which is rotatable only in one direction.
In another example of the conventional automatic original feeding and discharging device, a switch back conveyor route is arranged above an outlet of a main conveyor route from which a conveyor route for turned over original papers is diverged. In the turn over operation mode, an original paper after being copied is guided to the switch back conveyor route and reversed the conveying direction to run back the main conveyor route, then being guided to the turned over original paper conveyor route diverged from the main conveyor route and discharged from an outlet of the conveyor route.
Still another example of the conventional automatic original feeding and discharging device is disclosed in Japanese Unexamined Patent Publication No. 61-80144. This example comprises a discharge roller which can be selectively driven in either direction forward or backward.
In the turn over operation mode, the discharge roller is driven backward to switch back the original paper using the main conveyor route in common as a switch back conveyor route. After turning the original paper over, the discharge roller is again driven forward to discharge the turned over original paper out of the device.
However, the above mentioned conventional automatic original turning over devices involve problems that the size of the device becomes large because of the provision of the special switch back conveyor route in addition to the main conveyor route or that the operation control of the switch back movement is very complicated in the case wherein the discharge roller which is rotatable both forward and backward is used.
Also, the conventional automatic original turning over and discharging device disclosed in Japanese Unexamined Patent Publication No. 61-80144 mentioned above has a problem that when one of original papers successively conveyed in series at a regular interval is accidentally delayed by being slipped or obliquely fed, the preceding delayed paper is prevented from being smoothly conveyed backward when the paper is to be turned over since the preceding delayed paper and the subsequent paper pass each other in the opposite directions in the common main conveyor route when the preceding paper is switched back in the turn over operation mode.